1. Technical Field
The disclosure generally relates to heat transfer apparatuses, and particularly to a flat heat pipe with high heat transfer performance and a method for manufacturing the flat heat pipe.
2. Description of Related Art
Heat pipes are widely used in various fields for heat dissipation purposes due to their excellent heat transfer performance. One commonly used heat pipe includes a sealed tube made of heat conductive material, and a working fluid contained in the sealed tube. The working fluid conveys heat from one end of the tube, typically referred to as an evaporator section, to the other end of the tube, typically referred to as a condenser section. Preferably, a wick structure is provided inside the heat pipe, lining an inner wall of the tube, and drawing the working fluid back to the evaporator section after it condenses at the condenser section.
During operation, the evaporator section of the heat pipe maintains thermal contact with a heat-generating electronic component. The working fluid at the evaporator section absorbs heat generated by the electronic component, and thereby turns to vapor. Due to the difference in vapor pressure between the two sections of the heat pipe, the generated vapor moves, carrying the heat with it, toward the condenser section. At the condenser section, the vapor condenses after transferring the heat to, for example, fins thermally contacting the condenser section. The fins then release the heat into the ambient environment. Due to the difference in capillary pressure which develops in the wick structure between the two sections, the condensate is then drawn back by the wick structure to the evaporator section where it is again available for evaporation.
Typically, the wick structure is attached to the whole inner wall of the tube from the evaporator section to the condenser section. As a result, a space in the heat pipe for the vaporized working fluid to flow through may be inadequate. This leads to a high flow resistance for the working fluid, and thereby retards the heat transfer capability of the heat pipe.
What is needed, therefore, is a flat heat pipe that has high heat transfer performance, and a method for manufacturing the flat heat pipe.